Claims
- 1. An aqueous polishing composition having abrasive particles and water of basic pH to remove a barrier layer from a dielectric layer by CMP, the aqueous polishing composition further comprising: solely polar molecules each having multiple, polar bonding sites forming respective bonds with bonding groups on a hydrated dielectric layer of a semiconductor substrate, to form an hydrophilic protective film of the solely polar molecules on the dielectric layer.
- 2. An aqueous polishing composition as recited in claim 1 wherein, the solely polar molecules comprise polyethyleneimine of an average molecular weight of 800,000.
- 3. An aqueous polishing composition as recited in claim 1, further comprising: the average molecular weight of the solely polar molecules being selected to adjust a selectivity ratio, of barrier layer removal rate to dielectric layer removal rate, to remove a controlled amount of the dielectric layer when CMP is performed to remove the barrier layer.
- 4. An aqueous polishing composition as recited in claim 1, further comprising: the concentration of the solely polar molecules being selected to adjust a selectivity ratio, of barrier layer removal rate to dielectric layer removal rate, to remove a controlled amount of the dielectric layer when CMP is performed to remove the barrier layer.
- 5. An aqueous polishing composition as recited in claim 1 wherein, the molecules are derived from polymer compounds, including but not limited to; polyacrylamide, polyvinylpyrrolidone, polyethyleneimine, and polyethyleneimine.
- 6. An aqueous polishing composition having abrasive particles and water of basic pH to remove a barrier layer from a dielectric layer by CMP, the aqueous polishing composition further comprising: molecules derived from polymer compounds, including but not limited to; polyacrylamide, polyvinylpyrrolidone, polyethyleneimine, and polyethyleneimine, each having multiple, polar bonding sites forming respective hydrogen bonds with silanol bonding groups on a hydrated silicon dielectric layer of a semiconductor substrate, which form an hydrophilic protective film of the molecules on the dielectric layer.
- 7. An aqueous polishing composition as recited in claim 6 wherein, the solely polar molecules comprise polyethyleneimine of an average molecular weight of 800,000.
- 8. An aqueous polishing composition as recited in claim 6, further comprising: the average molecular weight of the solely polar molecules being selected to adjust a selectivity ratio, of barrier layer removal rate to dielectric layer removal rate, to remove a controlled amount of the dielectric layer when CMP is performed to remove the barrier layer.
- 9. An aqueous polishing composition as recited in claim 6, further comprising: the concentration of the solely polar molecules being selected to adjust a selectivity ratio, of barrier layer removal rate to dielectric layer removal rate, to remove a controlled amount of the dielectric layer when CMP is performed to remove the barrier layer.
- 10. A method of adjusting a selectivity ratio, of barrier layer removal rate to dielectric layer removal rate, for a polishing composition used in a process of chemical mechanical polishing to remove a barrier layer from a dielectric layer on a semiconductor wafer, comprising the steps of:
providing the polishing composition with a concentration of molecules having multiple bonding sites with bonding groups on the dielectric layer, and an average molecular weight selected to adjust the selectivity ratio, such that a controlled amount of the dielectric layer is removed when chemical mechanical polishing removes the barrier layer from the dielectric layer on a semiconductor wafer, and performing chemical mechanical polishing with the polishing composition and with a polishing pad to remove the barrier layer from the dielectric layer on a semiconductor wafer, and to remove the controlled amount of the dielectric layer.
- 11. The method as recited in claim 10, further comprising the step of: selecting the average molecular weight to adjust the selectivity ratio, such that a minimized controlled amount of the dielectric layer is removed; and wherein, the step of performing chemical mechanical polishing further comprises the step of; performing chemical mechanical polishing to remove the barrier layer from the dielectric layer on a semiconductor wafer, and to remove the minimized controlled amount of the dielectric layer.
- 12. A method of adjusting a selectivity ratio, of barrier layer removal rate to dielectric layer removal rate, for a polishing composition used in a process of chemical mechanical polishing to remove a barrier layer from a dielectric layer on a semiconductor wafer, comprising the steps of:
providing the polishing composition with a concentration of molecules having multiple bonding sites with bonding groups on the dielectric layer, and a concentration in the polishing composition selected to adjust the selectivity ratio, such that a controlled amount of the dielectric layer is removed when chemical mechanical polishing removes the barrier layer from the dielectric layer on a semiconductor wafer, and performing chemical mechanical polishing with the polishing composition and with a polishing pad to remove the barrier layer from the dielectric layer on a semiconductor wafer, and to remove the controlled amount of the dielectric layer.
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation in part of application Ser. No. 09/759583 filed Jan. 12, 2001.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09759583 |
Jan 2001 |
US |
Child |
10005253 |
Dec 2001 |
US |